How to Write a Design Brief That Gets You What You Want

Here’s how to write a design brief that gets you what you want the first time.

What a good design brief actually is

Not a specification document. Not a wireframe. Not a list of pages you want.

A good design brief answers three questions clearly:

1. What is this design for?
2. Who is it for?
3. What does success look like?

Everything else is either scope or content. Those go in different documents.

The three questions in detail

What is this design for?

Not “a new website.” That’s not a purpose, that’s a deliverable.

The right answer: “A new website whose main job is converting founder-led B2B SaaS visitors into booked discovery calls.”

Notice what changed. Now the designer knows:

• The primary user (founder-led B2B SaaS visitors)
• The main conversion event (booked discovery calls)
• The type of visitor (business owners, not consumers)

That single sentence guides every design decision downstream.

Who is it for?

Not “our customers.” That’s too broad.

The right answer: “Series A to Series B B2B SaaS founders and CTOs, US-based, 20 to 200 employees, currently spending on paid ads without much conversion, technically literate but time-poor.”

Now the designer knows:

• The persona is technical (can handle detail)
• Time poor (design must load fast, be scannable)
• Paying for other channels (justifying spend matters)
• Growth-stage (past MVP, before enterprise)

Every design choice can now serve this specific person.

What does success look like?

Not “a beautiful site.” Beautiful is table stakes, not success.

The right answer: “A site that increases discovery call booking rate from 1.2% to 3%+ within 60 days of launch, without hurting current organic traffic.”

Now everyone has a measurable outcome. The designer can prioritize decisions that serve the metric. You can evaluate the work against a clear standard.

What to include in a design brief

• Purpose of the design (as above)
• Primary user (as above)
• Success metrics (as above)
• 3 to 5 competitors or reference sites you admire, with a sentence each on what specifically you like
• 2 to 3 sites you actively dislike, with what specifically bothers you (this is often more useful than the “likes”)
• Brand assets: logo, colors, typography if defined
• Content status: do you have final copy, or do you need help with it?
• Technical constraints: preferred CMS, must-have integrations, hosting
• Real timeline (not aspirational)
• Real budget range (not “get back to us with a number”)

What to skip in a design brief

Specific solutions: Don’t tell the designer to “add a hero image with a video background and 3 CTA buttons.” Tell them what you’re trying to achieve. Let them propose solutions.

Design opinions dressed as requirements: “Make it modern” isn’t a requirement. “Doesn’t feel dated within 24 months” is closer, but still fuzzy. Skip vague adjectives.

Committee input: If 15 people at your company have opinions about the site, do the alignment before the brief goes out. Designers can’t design for 15 conflicting stakeholders.

Endless disclaimers: “We know we probably need to also think about X, and maybe Y, and Z is important too.” Prioritize. Say what matters most. Save “and also” for later conversations.

The section most briefs skip that matters most

What we can’t do.

A brief that includes clear constraints outperforms a brief that pretends anything is possible.

Example: “We can’t move the site to a new CMS this quarter because our marketing team just finished training on the current one.” That constraint changes the entire scope. Better to say it upfront.

Or: “We can’t add live chat because our support team doesn’t have coverage.” Now the designer knows to design around that.

Constraints aren’t limitations. They’re clarity.

The section most briefs skip that also matters

What our brand actually sounds like.

Most briefs describe brand visually. Colors, fonts, logos. Few describe brand tonally.

Include 2 to 3 examples of your writing that feel true to how you want to sound. Not aspirational voice. Actual voice from your best content.

The designer will thank you. The designer’s copywriter will thank you more.

Common brief mistakes

1. Writing the brief for the audience you have, not the one you want.

If your current site attracts SMB accounts and you want to attract enterprise, don’t write the brief for SMB visitors. Write it for the enterprise buyers you want to attract.

2. Asking for too much on the first project.

A brief that says “rebuild our entire site, migrate to a new CMS, integrate with these 8 tools, and add e-commerce” is not one project. It’s four. Each will suffer.

Prioritize. If you must do multiple things, sequence them.

3. Being vague about content.

“We’ll figure out the content later” is where projects die. Designers can’t design pages without knowing what will fill them.

Either provide content, commit to providing content by a specific date, or hire copywriting as part of the engagement.

4. Skipping the “why now” question.

Why is this project happening this quarter and not next? Understanding the timing pressure helps the designer make trade offs.

Length

A good brief is usually 2 to 5 pages. Under 2 pages and you’re probably missing important context. Over 5 pages and you’re probably including things that should live elsewhere.

If you find yourself writing 10 pages, you’re mixing brief, scope, and specification. Separate them.

When to write the brief yourself vs. when to have the agency help

Write it yourself if:

• You have clear positioning and know your users well
• You’ve done similar projects before
• Your team can align on the answers to the three questions

Have the agency help if:

• You’re not sure what you actually need
• Your team can’t align on priorities
• The project is complex enough that scoping needs expert input

Agencies who help you scope well often deliver better work because the brief becomes a shared document, not an adversarial one.

Working on a project brief and want a second set of eyes? We often help clients tighten briefs before formal engagement starts. Book a 20 minute call.